内容摘要：Sources familiar with the visit suggested several topics that could dominate the conversation.

Sources familiar with the visit suggested several topics that could dominate the conversation.

The former chief technology officer speaks ruefully about his long career trying to bring a revolutionary aerospace engine to fruition at UK firm Reaction Engines.The origins of Reaction Engines go back to the Hotol project in the 1980s. This was a futuristic space plane that caught the public imagination with the prospect of a British aircraft flying beyond the atmosphere.

The secret sauce of Hotol was heat exchanger technology, an attempt to cool the super-heated 1,000C air that enters an engine at hypersonic speeds.Without cooling this will melt aluminium, and is, Mr Varvill says, "literally too hot to handle".Fast forward three decades to October 2024 and Reaction Engines was bringing the heat exchanger to life at sites in the UK and US.

UK Ministry of Defence funding took the company into hypersonic research with Rolls-Royce for an unmanned aircraft. But that was not enough to keep the business afloat.Rolls-Royce declines to go into details about Reaction's collapse, but Mr Varvill is more specific.

"Rolls-Royce said it had other priorities and the UK military has very little money."

Aviation is a business with a very long gestation time for a product. It can take 20 years to develop an aircraft. This unforgiving journey is known as crossing the Valley of Death.which sparked a shopping frenzy.

And while users consume the videos TikTok has also become a platform to buy and sell a bite of the action.Kate Lancaster's two children both have milk allergies and she regularly posts advice on TikTok as The Dairy Free Mum.

She thinks TikTok has a responsibility to ensure all products sold on its shopping platform meet safety and labelling standards."It's completely unacceptable and really worrying. Failing to provide ingredient information is potentially very dangerous, and it feels like a complete disregard for the safety of those living with food allergies," she said.